<template>
  <div class="login_container">
    <div class="login_box">
      <!-- 头像区域 -->
      <div class="avatar_box">
        <img
          src="http://coderblx.gitee.io/blog/images/head_portrait.jpg"
          alt=""
        />
      </div>
      <!-- 登录表单区域 -->
      <el-form
        ref="loginFormRef"
        :model="loginForm"
        :rules="loginFormRules"
        label-width="0px"
        class="login_form"
      >
        <!-- 用户名 -->
        <el-form-item prop="username">
          <el-input
            v-model="loginForm.username"
            prefix-icon="el-icon-user"
          ></el-input>
        </el-form-item>
        <!-- 密码 -->
        <el-form-item prop="password">
          <el-input
            v-model="loginForm.password"
            prefix-icon="el-icon-lock"
            type="password"
          ></el-input>
        </el-form-item>
        <!-- 按钮区域 -->
        <el-form-item class="btns">
          <el-button type="primary" @click="login">登录</el-button>
          <el-button type="info" @click="resetLoginForm">重置</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>

<script>
export default {
  name: "Login",
  data() {
    return {
      // 这是登录表单的数据绑定对象
      loginForm: {
        username: "admin",
        password: "123456",
      },
      // 这是表单的验证规则对象
      loginFormRules: {
        // 验证用户名是否合法
        username: [
          { required: true, message: "请输入用户名称", trigger: "blur" },
          { min: 3, max: 5, message: "长度在 3 到 5 个字符", trigger: "blur" },
        ],
        // 验证密码是否合法
        password: [
          { required: true, message: "请输入登录密码", trigger: "blur" },
          {
            min: 6,
            max: 15,
            message: "长度在 6 到 15 个字符",
            trigger: "blur",
          },
        ],
      },
    };
  },
  methods: {
    // 点击重置按钮，重置登录表单
    resetLoginForm() {
      this.$refs.loginFormRef.resetFields();
    },
    login() {
      this.$refs.loginFormRef.validate(async (valid) => {
        if (!valid) {
          return;
        }
        const { data: res } = await this.$http.post("login", this.loginForm);
        if (res.meta.status !== 200) {
          this.$message.error("登陆失败");
        } else {
          this.$message.success("登陆成功");
          // 1. 将登录成功之后的 token,保存到客户端的 sessionStorage(会话机制/只在当前页面生效)中 localStorage(持久话机制/关闭页面也不会忘记数据)
          //   1.1 项目中除了登录之外的API接口,必须在登录之后才能访问
          //   1.2 token 只应在当前网站打开期间生效, 所以将 token 保存在 sessionStorage中
          window.sessionStorage.setItem("token", res.data.token);
          // 2. 通过编程式路由导航跳转到后台主页,路由地址是 /home
          this.$router.push("/home");
        }
      });
    },
  },
};
</script>

<style lang="less" scoped>
.login_container {
  background-color: #2b4b6b;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.login_box {
  width: 450px;
  height: 300px;
  background-color: #fff;
  border-radius: 5px;
  position: relative;

  .avatar_box {
    height: 130px;
    width: 130px;
    background-color: #fff;
    border: 1px solid #eee;
    border-radius: 50%;
    padding: 8px;
    position: absolute;
    left: 50%;
    transform: translate(-50%, -50%);

    img {
      height: 100%;
      width: 100%;
      background-color: #fff;
      border-radius: 50%;
    }
  }
}

.login_form {
  width: 100%;
  padding: 20px;
  position: absolute;
  bottom: 0;
  box-sizing: border-box;
}

.btns {
  display: flex;
  justify-content: flex-end;
}
</style>
